Striker mechanism for door chime



June 12, 1962 MCEVOY STRIKER MECHANISM FOR DOOR CHIME 3 Sheets-Sheet 1 Filed Dec. 30, 1959 INVENTOR.

A T ra/eA/eys.

June 12, 1962 .1. MOEVOY STRIKER MECHANISM FOR DOOR CHIME 5 Sheets-Sheet 2 Filed Dec. 50, 1959 June 12, 1962 J. MCEVOY STRIKER MECHANISM FOR DOOR CHIME 3 Sheets-Sheet 3 Filed Dec. 30, 1959 tates atent STRIKER MECHANESM FOR HOUR (II-HME .Foseph McEvoy, Batavia, @hio, assignor to Nutone, Inc, Cincinnati, (Elsie, a corporation of New York Filed Dec. 3t}, 1959, Ser. No. 862,373 1 Claim. (til. 16-14t) This invention relates to an improvement in door chimes, and in particular to an improvement in the striker mechanism which causes the sounding elements of the chime to ring.

In chimes of the type to which this invention is directed, the striker mechanism is mechanically actuated by a push button located on the outside of the door or partition, the striker mechanism being located as an integral unit on the inside of the door in direct alignment with the push button.

It is conventional to achieve the desired chime eiiect by employing tone bars which typically comprise flat strips of steel mounted so as to vibrate at a musical tone when struck sharply. The particular tone created, of course, depends on the length, width and material of the tone bars; in door chimes which sound two notes successively, one tone bar is somewhat longer than the other, to create the lower note.

The striker mechanism is required to transmit or transform the short linear push imparted by the operator to the button into a more complex motion whereby each tone bar is given, in succession, a sharp ringing tap. An impulsive strike is attained through the use of a striker head, a relatively heavy bob usually mounted in pendulum fashion between the tone bars. The striker head is caused to swing rapidly first to hit one tone bar, then the other, and then to return to a rest position, upon release of the push button. This invention, therefore, is particularly directed to the mechanism whereby this rapid motion is imparted to the striker head in the space between the tone bars.

A further aspect of the invention arises from the fact that once the striker head is brought into ringing contact with the tone bars it must not be permitted to remain in contact with the tone bar else the vibrations set up will be damped. In other words, the mechanism must be such that the striker head is permitted only a momentary, ringing contact with the tone bars, no matter whether the button is pushed gently or forcefully.

The present invention provides a striker mechanism which meets these conditions, which is at once simple and reliable because it is comprised of few moving parts, which may be fabricated relatively inexpensively. The invention is easily installed, requiring that only a single drill hole be made.

The principle of the invention, reduced to its fundamentals, is that the striker head is given the desired impulsive swinging motion by so moving a spring attached to it that the spring applies a torque to the striker head about its pivot point first toward one tone bar, and then toward the other. By a unique mechanical arrangement, this spring is moved from side to side of the pivot point of the striker arm as the button is pushed. This principle may be more fully explained by reference to the accompanying drawings, in which:

FIGURE 1 is a front elevation of a door having a chime embodying the present invention installed upon it;

FIGURE 2 is a perspective view, partly broken away, showing generally the manner in which the chime is mounted upon the door;

FIGURE 3 is :an enlarged section through the chime taken on line 3-3 of FIGURE 1;

FIGURE 4 is an elevation of the striker mechanism with the cover removed;

FIGURE 5 is a horizontal section taken on line 55 of FIGURE 4;

FIGURE 6 is a perspective view, partly broken away, showing the details of the striker mechanism;

IGURE 7 is a diagrammatic horizontal section taken on line 77 of FIGURE 4 illustrating the manner in which the striker is actuated when the chime button is pushed;

FIGURE 8 is a detailed diagrammatic elevation show ing the motion of the striker mechanism when the button is pushed;

FIGURE 9 is similar to FIGURE7 but illustrates the motion of the striker mechanism upon release of the button;

FIGURE 10 is similar to FIGURE 8 but illustrates the return motion of the striker to its normal position upon release of the button; and

FIGURE 11 is a diagrammatic view of a modified arrangement of the spring which actuates the striker.

In FIGURE 1 is shown a door 10 having mounted on it a chime 11 constructed in accordance with this invention. The particular construction of the door 10 is of no importance as regards the invention, and although the door 10 illustrated in the drawings is of panel construction, it may equally well be of other construction.

As can be seen from FIGURE 2, which shows the chime 11 as installed, the chime 11 is operated by a push button 12 which is part of an assembly 13 mounted on the outside surface 14 of the door 10. The bush button 12 is mechanically coupled through the door 10 to a second assembly, generally indicated at 15, which includes tone bars, striker and striker mechanism, and housing resonator, and which is mounted on the inside 16 of the door. The improvement of this invention is particularly directed to the assembly 15.

As can best be seen in FIGURE 3, the push button assembly 13 comprises a mounting plate 17 adapted to be mounted on the door 10 by means of screws 18. This plate 17 is provided with a pair of outwardly extending ears 2t 20, each ear presenting a horizontal slot 21. The push button 12 for actuating the chime striking mechanism 15 is provided with a lateral stud 22 on each side. These studs 22 are engaged in the slots 21 whereby the push button 12 is confined to movement in a direction perpendicular to the place of the door 10. A cover plate 23 encloses this assembly, the push button 12 extending through an opening in the cover plate 23 so as to be accessible to the operator. The cover plate 23 is removably attached to the mounting plate 17 by means of screws 25 which engage tabs 26 formed on the mounting plate 17. If desired, the cover plate 23 may be provided with a Windowed slot 24 to hold a card bearing the name of the occupant,

Extending from the push button 12 through a hole 27 in the door It is an elongated connector 28, the purpose of which is to transmit the linear motion imparted to the button 12 by the operator to the striker mechanism 15 on the other side of the door 10 whereby the chime 11 is rung. As will be explained more fully hereinafter, the connector 28 is pivotally connected to a vertical pin 30 of the striker mechanism 15, as is best shown in FIGURE 6, the pin 30 extending through one of a series of holes 29 in the connector. It is preferable, although not necessary, that the connector 28 be made of a flat strip of metal and contain a number of holes 29 for engaging pin 30 in order that the chime 11 may be installed upon doors in a range of thicknesses; when the assembly 13 is mounted upon a relatively light, thin door, the pin 30 is inserted through a hole 29 which is close to the button, and the unneeded portion of the connector 28 may simply be broken off in the manner shown in FIGURE 6.

The chime mechanism 15 to which the invention is particularly directed is best illustrated in FIGURES 3, 4 and 5. This mechanism 15 is mounted on a back plate 31 which is secured to the inside 16 of the door 10, as by means of the screws 32 shown in FIGURE 4. The mechanism 15 is enclosed by a conventional resonator housing 33 which may be simply a metal enclosure secured to the back plate 31 at one end by means of a tab 34 formed on the plate 31 which engages a co-acting slot provided at one end of the housing 33, and by means of a screw 35 at the other end. The details of the resonator 33 and of its attachment are not a part of the invention, resonators being well known in the art.

Tone bars 36 and 37 are mounted in parallel relationship on supports 38 extending outwardly from plate 31 adjacent the lateral edges thereof. To provide a twotone chime, one tone bar (36) is shorter than the other. Following conventional practices the bars 36 and 37 are mounted from the supports 38 on rubber grommets 39.

Positioned between the tone bars 36 and 37 and adjacent their upper ends, a pair of parallel, horizontal pivot cars 40 extend outwardly from plate 31. These are drilled to present a pair of openings in vertical alignment with one another. A gate which is generally designated by 41 is provided with a pair of axles 42 at one side. These axles 42 are engaged with the openings in the pivot ears 40, so that the gate 41 is rotatable to a limited extent about an axis which is substantially parallel to the tone bars 36 and 37.

Gate 41 is generally L-shaped, as is shown in FIGURE 6, and comprises a vertical main portion 43 and a flange portion 44 which extends outwardly from the main portion 43. When the gate 41 is caused to rotate about its vertical axis from an initial position in which it resides against the back plate 31, the vertical portion 43 of the gate 41 swings through an are which, for a short distance, is substantially directly outward "from the back plate 31, While the flange 44, at an angle to the vertical portion of the gate 41, swings through an arc which is more nearly parallel to the plane of the back plate 31, or from right to left in FIGURE 4. At its outer end the flange 44 is engaged with a tension spring, as is more fully explained below.

The vertical part of the gate 41 is provided with an upstanding pin 30, which engages an opening 29 in the push button connector 28, as previously described. Preferably pin 36 is formed in a central opening in the gate 41 as shown in the drawings, but the pin 30 may be located at any point which does not lie on the axis of the gate 41.

When the button 12. is pushed, the connector 28 transmits this push to the gate 41 through pin 30, causing the gate 41 to rotate about its vertical axis in a clockwise direction as shown in FIGURE 7. It is by means of the gate 41, therefore, that the linear motion of the button 12 is transformed to a motion which is effective to properly acuate the striker arm.

A pivot member 46 extends outwardly from the back plate 31 between the tone bars 36 and 37 and below the flanged portion 44 of the gate 41. This member presents a simple knife edge pivot which is substantially perpendicular to the plane of the back plate 31. A striker arm 47 is mounted so as to swing in a vertical plane about pivot member 46.

In a preferred embodiment, the striker arm 47 comprises an elongated arm 47a having a weighted head 48 at its lower end. The head 48 is encircled by a hard rubber washer 49 for making ringing contact with the tone bars 36 and 37. At its upper end, the arm 47 has a V-shaped notch 47b whereby it engages the pivot member 46. The striker arm 47 is held upwardly against, rather than suspended from, the knife edge pivot 46, by an acuating spring 50. This spring 50 is secured at one end to a mounting lug 51 which extends from the back plate 31 at a point which is above pivot member 46 and which is nearer to one tone bar than the other. Spring 59 is engaged with flange 44 at point 45 near the tip of the flange 44, as by the notch 47b shown. As its lower end, the spring 50 is secured to the striker arm 47 at point 52 below the pivot member 46. When so connected, spring 511 is under tension. As can best be seen in FIGURE 4, point 45 at which spring 50 is connected to flange 44 is so positioned that, when the button 12 is not depressed and the gate 41 r-ests against the back plate 31, the lower part of the spring 56, that is, the part between the points of connection to the flange 44 and to the striker arm 47 lies to the right of the pivot member 46, so that the spring 51 exerts a counter-clockwise torque on the striker arm 47 about pivot member 46, urging the striker head 48 toward tone bar 37.

The upper part of the spring 5%, that part between the point of connection to the flange (45) and lug 51, exerts a counter-lockwise pull on the gate 41 about its vertical axis so that the gate 41 is normally held against the back plate 31. Since connector 28 is coupled to the gate 41 through pin 39, this part of the spring 50 indirectly urges the connector 28 and push button 12 outwardly, so that the push button 12 is normally in an undepressed condition. It can be seen that the two parts of the single spring 50 thus act as separate springs and have difierent functions, the upper part returning the striker 47 to its initial position, and the lower part swinging the striker 47 about its pivot 46 as the gate 41 is rotated against the bias of the upper spring 50.

Striker arm stops 53 and 54 extend outwardly from the back plate 31 in such position as to be engagable with an arresting bar 55 on the underside of the striker arm 47, arresting the striker arm 47 at both the left and the right extremes of its swing toward the tone bars 36 and 37 a short distance before it contacts the tone bars 36 and 7, as at 56 in FIGURE 4.

To permit only impulsive contact between the striker head 48 and the tone bars 36 and 37, each stop 53 and '54 is provided with a resilient pad 57, which may be of sponge rubber. Thus, as the striker arm 47 is swung counter-clockwise about pivot 46, that is, to the right in FIGURE 6, it moves until the arresting bar 55 comes into contact with the pad of stop 54. This contact occurs a moment prior to the time at which the striker head 48 actually contacts the tone bar; the inertia of the striker head 48 causes the stop 54 to yield slightly and the pad 57 to be compressed, thereby permitting the striker head 48 to come into ringing contact with the tone bar 37, after which the stop 54- and pad 57 urge the striker head 48 a slight distance away from the tone bar 37, so that the vibrations set up are not damped.

A felt pad 58 is mounted on a finger-like extension 60 of the gate 41, so that the return of the gate 41 to a position in which it bears against the back plate 31, following release of the push button 12 is quiet.

When the push button 12 is not depressed, the stretched condition of spring 50 causes it to actuate the respective parts of the assembly to positions whereby it is stretched the least amount. As noted, the state of least elongation of the two parts of the spring 50 is that condition shown in FIGURE 4-, in which the gate 41 is pressed against the back plate 31, and the lower part of the spring 50 lies entirely to the right of a line drawn from lower point of attachment 52 to pivot member 46. The spring 50 in this attitude exerts a torque on the striker arm 47 tending to turn it counter-clockwise around pivot 46, but this torque is counter-balanced by, stop 54 which bears against the arresting bar 55 on the striker arm 47, thereby holding the arm in the position shown.

The operation of the chime when the button 12 is depressed is as fol-lows:

As can best be seen in FIGURES 7 and 8, when the push button 12 is depressed, it moves toward plate 17, its motion being guided by the slots 21 which mount the studs 22 carried by the button 12. Connector 28 moves with the button 12. Since the connector 28 is pivotally coupled to gate 41 by the pin 30, the linear movement of the connector 28 is transformed into rotation of the gate 41 about the vertical axis defined by its points of connection 42, 42 to the pivot ears 40. In FIGURE 7, this rotation is in a clock-wise direction. The upper part of the spring 50 resists this rotation and tends to return the gate 41 and button 12 to their original positions.

As the gate 41 turns in this manner, the flange portion 44 of the gate 41 swings through its own are. Precisely, the flange 44 swings from an initial position in which it was to the right (in FIGURE 4) of striker pivot member 46, over the pivot, to a new position at the left of the pivot when the button 12 is fully depressed.

Because of its attachment to the flange at 45, the lower part of spring 50 is constrained to move with the flange 45 in this arc-like path. As it moves from its initial position, the spring 50 is successively more stretched, becoming the most stretched at the moment when the lower part of the spring 50 lies directly over the line connecting pivot edge 46 and point 52. Throughout this phase of its motion the spring 50 at all times exerts a counterclockwise torque on the striker arm 47 thereby continuing to hold the arm 47 against stop 54, since the spring 50 is to the left of pivot member 46.

When the push button 12 is further depressed, the spring 50 moves past pivot member 46, so that it lies to the left of the line connecting points 52 and 46, it then exerts a clockwise torque on the striker arm 47. Because of the relatively stretched condition of the spring 5ft at this time, the striker 48, in response to this torque, is rapidly swung away from stop 54 towards stop 53, as shown in FIGURE 8. As it comes into contact with stop 53, it compresses the rubber bumper 57 mounted thereon, and rings the left tone bar 36. The tone bar 36 absorbs the momentum of the striker head 48, and the striker is then pushed away from the tone bar 36 by the bumper 57, allowing the tone bar 36 to ring. The housing 33, as is well understood in the art, resonates to the sound thus generated.

As long as the button 12 remains fully depressed, the chime elements remain in this attitude, in which the striker arm 47 rests against stop 53. However, the upper part of the spring 50, between point 51 and the flange 45, is now highly stretched, so that when the motivating force is released from the button 12, this part of the spring 50 urges the flange 45 to the right toward its original position. This, in turn, urges the push button 12 outwardly again.

Until point 45 swings to the right in response to this force and moves past pivot 46, the spring 50* is to the left of the line between points 52 and 46, and so continues to urge the striker arm 47 clockwise against stop 53. When the flange 45 and spring 50 move to the right of that line, however, the torque becomes a strong counter-clockwise torque, causing the striker arm 47 to be swung rapidly toward tone bar 37, which it rings in like manner to that already described, providing the desired two note effect.

Thus, the tension of the upper portion of the spring 50 which is between point '45 and the fixed lug 51 provides the primary force which urges the striker 48, gate 41 and button 12 toward their normal positions, while the lower part of the spring 50 provides the force which swings the pivot arm 47 into contact with the tone bars 36 and 37.

As can be seen from the foregoing description, the chime 11 is actuated simply by causing a spring 50 to exert first a clockwise, and then a counter-clockwise, torque on the striker 48. This, in turn, is caused by the swinging of the gate flange 45, to which the spring 56 is attached, from a normal position on one side of the point 46 about which the striker 48 pivots, to a position on the other side of that point, and back again. It can be appreciated that the invention may likewise be made to operate by reversing the respective elements from the positions shown in the drawings, so that the striker 48 swings first from left to right, rather than vice versa, and

. 6 that such mode of operation is fully Within the scope of the invention.

In an alternative mode of construction, a spring 50 can be directly connected between the striker arm 47 and flange 44 to swing the striker 48 as specified without being connected to the back plate '31. The embodiment shown in the drawings is preferred, however, inasmuch as a single spring accomplishes both functions.

The chime 11 may quickly be installed on a door 10 or partition. To do so, once the mounting location has been selected, a hole 27 is drilled through the door 10 to receive the connector 28. The mounting plate 17 of the push button assembly 13 is mounted on the door with screws 18 in position such that when the button 12 is mounted between ears 20, the connector 28 will pass through the hole 27. The button 12 once mounted, its cover plate 23 is attached with screws 25. The back plate 31 of the inside chime striking assembly 15 is mounted so that pin 30 of the gate 41 is engaged with an opening 29 of the connector 28. To insure that pin 30 remains engaged with the connector 28, it is desirable that the back plate 31 be provided with a swingable stop such as that shown at 61 which may be moved, once the pin 30 is coupled to the connector 23, into a position whereby it prevents the connector 28 from jumping off the pin 30 when the button. 12 is pushed. The excess length of the connector 28 may then be broken off, the resonator housing 33 set in place with tab 34 and screw 35, to complete the installation.

Since the chime 11 is entirely mechanical in operation, no wires or source of electrical power are necessary. The mechanism is extremely simple and reliable.

Most of the component parts of the invention may be fabricated from sheet metal. Thus, the back plate 31 may be stamped from a single sheet, with stops 53 and 54, pivot 46, supports 38 and lug 51 formed integrally with it.

Having described my invention, I claim:

A mechanical door chime comprising, a base, a flat pivot member projecting perpendicularly from said base, said pivot member having a pair of opposite sides, said pivot member presenting an upwardly facing pivot edge adjacent said base and a downwardly facing pivot edge outwardly of said base, a striker arm terminating in a striker head, said striker arm presenting an upwardly opening notch in which the downwardly facing pivot edge of said pivot member is engaged, said striker arm presenting a downwardly opening notch which is offset inwardly from said upwardly opening notch and in which the upwardly facing pivot edge of said pivot member is engaged, a gate pivotally connected to said base above and to one side of said pivot member for rotation about a vertical axis, said gate including a flange portion which extends outwardly therefrom, said flange portion projecting outwardly beyond said striker arm and pivot member and terminating in a tip, the position of said tip with respect to said gate being such that said tip is normally positioned on the side of said pivot member opposite to the side on which said gate is connected to said base, push button means including a connector which is displaceable in the direction perpendicular to said base, said connector being pivotally connected to said gate at a point which does not lie on the axis of rotation of said gate, said gate there by being responsive to movement of said connector perpendicular to said base to rotate about said axis and swing the tip of said flange portion in an are from one side to the other side of said pivot member, a helical coil spring having one end connected to said base at a point above said tip and on the side of said pivot member opposite to the side on which said gate is connected to said base, said spring having another end which is connected to said striker arm adjacent said striker head, said spring being connected at a point between said ends to the tip of said flange portion whereby said spring urges said striker head outwardly from said base and holds the upwardly opening G notch of said striker arm upwardly against the downwardly facing pivot edge of said pivot member and whereby said spring also urges the tip of said flange toward a normal position on the side of said pivot member opposite to the side on which said gate is connected to said base, a pair of tone bars mounted by said base on opposite sides of said pivot member and positioned for ringing contact by said striker head, and stops mounted by said base on opposite sides of said pivot member for permitting only impulsive contact between said striker head and said tone bars.

References Cited in the file of this patent UNITED STATES PATENTS 

